Which of the following is both osmoregulator as well as nitrogenous product?

Options

A. `NH_(3)`
B. Urea
C. Uric acid
D. All of these

Answer

To solve the question "Which of the following is both osmoregulator as well as nitrogenous product?" we will analyze the options provided: ammonia, urea, uric acid, and determine which one fits both criteria.

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Osmoregulator**: A substance that helps to regulate the osmotic pressure of body fluids.
- **Nitrogenous Product**: Waste products that result from the metabolism of proteins and nucleic acids, primarily ammonia, urea, and uric acid.

2. **Identify the Nitrogenous Products**:
- **Ammonia**: Highly toxic and requires a lot of water to be excreted. It is not an osmoregulator.
- **Urea**: Less toxic than ammonia and is soluble in water. It is produced in the liver and is involved in osmoregulation.
- **Uric Acid**: Least toxic and excreted as a paste with minimal water loss. It does not play a significant role in osmoregulation.

3. **Evaluate Each Option**:
- **Ammonia**: Not an osmoregulator.
- **Urea**: Functions as both a nitrogenous waste product and an osmoregulator, as it helps maintain osmotic balance in the body.
- **Uric Acid**: Primarily a nitrogenous waste product, but does not significantly contribute to osmoregulation.

4. **Conclusion**:
- The correct answer is **Urea**, as it is both a nitrogenous waste product and serves as an osmoregulator.

### Final Answer:
Urea is both an osmoregulator and a nitrogenous product.

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